3D Printing the WordPress logo in two colors

My 3D printer only supports having one filament loaded at a time and that generally means the objects I print is one color. I wanted the WordPress logo (naturally) and two colors would be cool. I can print pieces in different plastics and assemble them but sometimes you want one piece. Good news! My printer’s open source firmware supports changing filaments before the print job is done. That let’s me start the base in one color but switch to another before the print is completed. Here’s how I did it.

I downloaded the WordPress logo to my PC via Wikimedia in SVG format. SVG is a vector format for images that can be scaled without losing sharpness. I loaded that into Fusion 360 and deleted the text to the right and just kept the round logo.

In Fusion 360 I scaled the logo to 50 mm diameter. I then extruded the white portions in the logo to 3 mm. The circle outline and the space between the parts of the “W” were extruded to 1.5 mm. I exported that to an STL file and loaded it into Simplify 3D. This is where it gets clunky.

For slicing 3D prints into a format the printer can understand I use software named Simplify 3D. It’s not opensource (or cheap) but it’s very extendable and saves me a lot of time.

Simplify 3D supports scripts that use regular expressions to locate text in the generated G-Code output file and make substitutions. In the generated code it also comments each layer of the print so there’s a “layer 8” text where I want to insert printer commands to swap filaments.

Figuring that I needed to modify layer 8 was a pain. There’s probably a well documented way to do it but I sent my G-Code output file to Octopi. I loaded the file but did not actually print it yet.

OctoPi comes with a built in G-Code viewer. I moved the slider up until I found that layer 8 was where I wanted the change filament commands inserted.

I then deleted that file from the OctoPi, went back to Simplify 3D and in the process settings I went to Scripts -> Starting Script and added this to the “Additional terminal commands for post processing” field.

{REPLACE "\n; layer 8, Z = " "; layer 8\nG28 Y0 X0\nM300 S0 P1000\nM25\nG92 E0\nG28 Y0 X0\n; layer 8 "}

And generated and updated G-Code file with additional commands that I sent to Octopi. I loaded up a spool of blue filament and began printing. Midway through the print the extruder moved to the home position (but did not change it’s height) and waited for me to change the filament. Once I did that I loaded Octopi’s web page on my phone, logged in and clicked “Resume”.

The resulting prints came out well and I repeated the process with the white filament first. The bottom is one color and the top is another at just the right place.

This hardly took me anytime at all. It’s not a fauxgo, it’s a legitimate SVG (well, I hope it is) representation of the WordPress logo. The blue is a bit off but I can be forgiven for that. The PLA material is listed as “Egyptian Blue” and it’s the closest I had on hand.

There’s probably an easier way to get the layer accurately without using Octopi but it works. If I find an easier way then I’ll update this post.

What I really want to do is print the badges for the WordPress teams such as Support, Docs, training, etc. That’d be cool and I may do that this weekend.

This all came about because my brother got his 3D printer working in two colors on the same layer. His printer has two extruders and can print one color next to the other on the same layer. My printer does not do that but I’ll catch up. Competition is good. 😉

Pi Zero W makes for a compact Retropie box

Of course I did this with a Pi Zero W. 😉

One of the reasons I like the Raspberry Pi is that it lets you take hardware and turn it into a dedicated purpose based appliance. Cheaply! And one of those uses is to make a retro game system. I've used the Raspberry Pi Zero before but I was hampered by the fact that it lacks network and Bluetooth access. To get that you need to purchase a USB hub, wifi dongle and if you want it an Bluetooth fob.

The new Pi Zero W addresses that and adds both wifi and Bluetooth on the small package. Once it's setup all you need is an HDMI cable and power. That's it.

Here's how I did it with an 8Bitdo Bluetooth SNES style controller.

  1. Download Retropie for the Zero onto another Pi Zero (non-wireless one, I have a few). I could not get the image to boot on the new device so I setup a hub with a wifi dongle and keyboard on an old version.
  2. After the image reboots to resize the file system then F4 to get out of Emulationstation and on the command line run this command.
 sudo apt-get update ; sudo apt-get -y upgrade ; sudo apt-get -y dist-upgrade ; sudo apt-get -y autoremove 

That will take a while to run and you will need to read part of the upgrade and press Q at a point. That annoys me as those commands should run unattended. Meh.

The purpose of this is to get the underlying Raspbian OS up-to-date.

  • When you’re done run sudo shutdown -h now and swap the old Pi Zero for the Pi Zero W. Unplug the wifi dongle, you don’t need it anymore. Boot up the Pi Zero W with the keyboard attached via the USB adapter.
  • Once it boots up press F4 to get back to the CLI and run these commands.
  •  cd RetroPie-Setup sudo ./retropie_setup.sh 

    And select "U Update all installed packages" with your arrow keys. I don't know if that step is necessary but I do it out of habit. I like making sure I have the latest updates. That will take a long while too and reboot when it's finally done.

  • Update your new 8Bitdo controller to the latest firmware. On my Windows PC I updated my SFC30 to firmware 2.71.
  • Boot your Pi Zero W and press F4 exit Emulationstation and manually run the retropie-setup script again. Follow these instructions to connect your 8Bitdo controller and don’t forget to do the UDEV part. Reboot as needed.
  • Transfer ROMs via the wifi to your new device. I find that NES, SNES and Genesis games work well. MAME is a bit of dicey but older games played satisfactorily.
  • Connect to HDMI TV and have lots of fun.
  • The final parts list came out to this.

    Pi Zero W$10
    8Bitdo SFC30 Bluetooth controller$30
    Pi Zero CaseI used one I 3D printed
    Mini-HDMI cable adapter$20
    2A micro USB power adapter$8

    I already had the cables and power supply but I'm trying to be complete. Not counting the case it's ~$70 for this one player setup.

    It's not a Raspberry Pi 3

    The overall experience is good and if you limit your retrogames to the older 8bit systems then you'll like it. But the Pi Zero W doesn't have all the CPUs and RAM of the bigger Raspberry Pi 3. The good Neogeo games won't play well. Sometimes sound suffers due to CPU use. Lag is a thing.

    But if you have the technical know how this beats the Nintendo Classic by a mile.